fresh water tank inadvertently filling

[schmitts]

'11 Winnebago Journey. My fresh water tank was filling with the fill valve in the 'normal' position. RV tech replaced the fill valve with a brass one. Same problem eventually developed. Had the water pump replaced. Same problem eventually came back, although I only used the pump once. When I use a pressure regulator, the filling of the fresh water tank is much slower, but there is insufficient water pressure in the rig. When I take the pressure regulator off the pressure comes back, but the filling of the tank is much faster. The RV tech suggested I buy a backflow regulator. Thoughts?

[Skip426]

If you don't know the park water pressure a regulator is a good idea , do you have an adjustable one with a gauge ?

The 12 volt pump , internal back flow preventer has pressure limits and it sounds like they're being exceeded , external valve is probably the answer.

[schmitts]

Originally Posted by Skip426

If you don't know the park water pressure a regulator is a good idea , do you have an adjustable one with a gauge ?

The 12 volt pump , internal back flow preventer has pressure limits and it sounds like they're being exceeded , external valve is probably the answer.

Thanks for your reply, Skip. No I don't have an adjustable gauge. I hear you on acquiring a better one. Do you think that's a solution to the inadvertent filling, or is a backflow preventer needed, and do you think the water pump is damaged?

[be-happy]

I had somewhat the same thing on my 07 Meridian. I found if I tryed to change water direction for normal to tank or tank to normal while under pressure it would not work. Once I took the pressure off (turned water hose off) the value worked the way it should.

[Duner]

My 2004 coach is nearly like yours and I 've had this problem a few times.
Two main causes:
1) The city water/fill valve is leaking. When you are connected to higher pressures, like 50-60 psi or more, and you move the valve under pressure it will wear out or tear the internal rubber moving part. After replacing it twice, now I always turn the pedestal water valve off first and release the pressure in the hose, then switch the city fill valve.

2) The check valves in the water pump are leaking. After years of use, the water pump will build up calcium and the check valves will leak. I got pretty used to taking the pump apart and soaking the valve assy in CLR solution to dissolve the build up. It would work for awhile and then I'd hear the pump run for a second every minute or two or three. I like the city pressure regulated to about 60-65 psi and that's what my water pump gives me when I'm dry camping. That much city water pressure usually back fills my water tank when I know the pump has been showing signs of check valve leakage. If I set the adjustable regulator down to 25-30 psi I don't get the tank back filling .... But I like more pressure for showers so I leave it at 65 psi.

So my permanent fix was to add a check valve between the pump and water tank. $7 for two check valves and now I have a spare. On my Chieftain this was about a 10 minute install. Your coach is going to have the same size water lines as my coach, so the valve below will work for you too.
https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1

[schmitts]

Originally Posted by Duner

My 2004 coach is nearly like yours and I 've had this problem a few times.
Two main causes:
1) The city water/fill valve is leaking. When you are connected to higher pressures, like 50-60 psi or more, and you move the valve under pressure it will wear out or tear the internal rubber moving part. After replacing it twice, now I always turn the pedestal water valve off first and release the pressure in the hose, then switch the city fill valve.

2) The check valves in the water pump are leaking. After years of use, the water pump will build up calcium and the check valves will leak. I got pretty used to taking the pump apart and soaking the valve assy in CLR solution to dissolve the build up. It would work for awhile and then I'd hear the pump run for a second every minute or two or three. I like the city pressure regulated to about 60-65 psi and that's what my water pump gives me when I'm dry camping. That much city water pressure usually back fills my water tank when I know the pump has been showing signs of check valve leakage. If I set the adjustable regulator down to 25-30 psi I don't get the tank back filling .... But I like more pressure for showers so I leave it at 65 psi.

So my permanent fix was to add a check valve between the pump and water tank. $7 for two check valves and now I have a spare. On my Chieftain this was about a 10 minute install. Your coach is going to have the same size water lines as my coach, so the valve below will work for you too.
https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1

Thanks for your reply, Duner. My fill valve and water pump have already been replaced. The fill valve is now brass, so I don't think that's failing. I think the problem is the water pump, which has hardly been used because we didn't travel during the pandemic. If the problem is the check valve inside the water pump, would that prevent the water pump from working? If not and my water pump is functional (which I haven't even tried for the past couple years), it would make sense to install a secondary valve as you did.

[Duner]

Originally Posted by schmitts

..... If the problem is the check valve inside the water pump, would that prevent the water pump from working? If not and my water pump is functional (which I haven't even tried for the past couple years), it would make sense to install a secondary valve as you did.

If you hear the pump run for just a second every few minutes, when no faucets are turned on then that is a sign that pump check valve is leaking. An external check valve will fix that too. The demand pump is designed to continuously keep pressure out to all the faucets, so a leaky check valve allows that pressure to escape back towards the water tank. When the pump senses the pressure too low, it runs momentarily to build the pressure back up.
My water pump is very quiet but it's right under the head of our bed. So we hear it burp at night when all is calm. Tells me a faucet is leaking or the pump check valve. I used to just kill the power to the pump at night and turn it back on in the morning. Well see how long the external check valve lasts before it too becomes leaky. I think the more you use it the longer it will last.

[schmitts]

Originally Posted by Duner

If you hear the pump run for just a second every few minutes, when no faucets are turned on then that is a sign that pump check valve is leaking. An external check valve will fix that too. The demand pump is designed to continuously keep pressure out to all the faucets, so a leaky check valve allows that pressure to escape back towards the water tank. When the pump senses the pressure too low, it runs momentarily to build the pressure back up.
My water pump is very quiet but it's right under the head of our bed. So we hear it burp at night when all is calm. Tells me a faucet is leaking or the pump check valve. I used to just kill the power to the pump at night and turn it back on in the morning. Well see how long the external check valve lasts before it too becomes leaky. I think the more you use it the longer it will last.

Thanks again, Duner. If I recall correctly, that was the exact problem I had (the pump cycling every couple minutes) that led to me replacing it. I think I'll go that route of seeing how it runs and adding an external valve if it cycles intermittently. Thanks for the good and clear advice.

[Iceman-31D]

Had the exact same problem this winter on my WBGO. Fairly high water pressure, then after awhile, my fresh water tank began to slowly fill on its own. Installed a check valve between pump and water tank and no more problems. Simple fix for your problem.

[cruizerEd]

Originally Posted by schmitts

'11 Winnebago Journey. My fresh water tank was filling with the fill valve in the 'normal' position.

Ours does that. It is the pump check valve for us. Replaced pump and it still does it randomly. I had a cut off valve put on the output side of the pump and if it starts backflowing I just turn it off.

Kind of a PTA because I will forget to turn it on when we need the pump but as soon as my wife tells me I we don't have water I go turn it on.

[weirba]

I have had 3 different coaches and each of them at one time or another had this same issue. As other people have suggested, it could be the city fill valve is worn and leaking, but more than likely it is leaking by the pump. The easy way to diagnose is if you are hooked up to city water and you notice your fresh tank filling up, then simply turn on the pump. Leave the pump on for a day or so, along with the city water, and see if the tank continues to fill. My guess is it will not. Sometimes all I need to do is cycle the pump once or twice for 10-15 seconds and that dislodges whatever debris is in the pump allows the city pressure to leak back.

The simple fix is to install a 0 pressure check valve. You can even buy one with sharkbite fittings, so it is very DIY friendly. Here is the Homedepot link:

https://www.homedepot.com/p/SharkBit...0LFA/202721919


It is a pretty simple fix.

[jerichorick]

Originally Posted by schmitts

'11 Winnebago Journey. My fresh water tank was filling with the fill valve in the 'normal' position. RV tech replaced the fill valve with a brass one. Same problem eventually developed. Had the water pump replaced. Same problem eventually came back, although I only used the pump once. When I use a pressure regulator, the filling of the fresh water tank is much slower, but there is insufficient water pressure in the rig. When I take the pressure regulator off the pressure comes back, but the filling of the tank is much faster. The RV tech suggested I buy a backflow regulator. Thoughts?

I had the same problem a few years back. I replaced the tank fill valve and that fixed the problem. It has small plastic legs on a spongy rubber insert. You are not supposed to move the valve to fill with water pressure on the hose. It puts too much strain on the legs and they break.
Shut the valve off. Remove the handle. Unscrew the knurled retainer nut. Pull the cartridge out. You can see the damage.
I used a brass ball valve replacement.

[Qui-Gon John]

Originally Posted by Duner

So my permanent fix was to add a check valve between the pump and water tank. $7 for two check valves and now I have a spare. On my Chieftain this was about a 10 minute install. Your coach is going to have the same size water lines as my coach, so the valve below will work for you too.
https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1

Can you describe better or show pics on where we could install this additional check valve? Is it the line coming from the Fresh Water Tank and going INTO the pump (supply for the pump). If so, I take it the valve should be installed so it does not allow any flow in that line the other way, from the pump to the tank.

[Qui-Gon John]

Originally Posted by jerichorick

I had the same problem a few years back. I replaced the tank fill valve and that fixed the problem. It has small plastic legs on a spongy rubber insert. You are not supposed to move the valve to fill with water pressure on the hose. It puts too much strain on the legs and they break.
Shut the valve off. Remove the handle. Unscrew the knurled retainer nut. Pull the cartridge out. You can see the damage.
I used a brass ball valve replacement.

Can you post a link to a replacement? I'd like to try replacing mine.